This invention relates generally to fuel-injected internal combustion engines, and more specifically it relates to a new and improved mounting of a fuel rail on an engine.
It is a known practice to mount a fuel rail directly on an engine, and this is typically called a "hard" mount. It has been observed that when certain fuel rails are mounted on certain engine intake manifolds by means of a "hard" mount, vibrations caused by the opening and closing of the electromagnetically-operated injectors and fuel flow pulsations can be transmitted directly to the manifold runners. Sometimes these vibrations may be deemed objectionable, or even detrimental. Accordingly in those situations, other than a "hard" mounting may be appropriate.
The obvious approach to providing vibration attenuation, or isolation, is by disposing some sort of elastomeric means between the fuel rail and the manifold. However, reliable, consistent, facile, and economical assembly of a fuel rail to a manifold on a mass-production basis is not inherently realized by the mere use of an elastomeric pad or the like. Often the objectional vibrations may be consistently and reliably attenuated to non-objectionable levels only by rather strict control of the manufacturing and assembly process. Accordingly, there is a need for obtaining consistent, reliable vibration attenuation and isolation while also minimizing the extent to which such strict control is required, and the present invention is directed to a means for attaining this end.
Once revealed, the invention is quite simple; yet, it provides reliable, consistent, facile, and economical assembly of a fuel rail to a manifold in a manner that provides improved vibration isolation by attenuating objectional vibrations. Moreover, the inventive principles are quite generic in that they are susceptible of application to different engine/fuel rail combinations for attainment of a particular vibration attenuation that is best-suited for each particular combination.
Principles of the invention will be explained in detail with reference to the accompanying drawing which presents a presently preferred exemplary embodiment in accordance with the best mode contemplated at this time for the practice of the invention. With this disclosure, the attributes of the invention will become apparent to the reader.